Represents the function object unary adapter. More...

#include <OpenMS/CONCEPT/UnaryComposeFunctionAdapter.h>

Inheritance diagram for UnaryComposeFunctionAdapter< OP1, OP2 >:

Public Member Functions
	UnaryComposeFunctionAdapter (const OP1 &o1, const OP2 &o2)
	Constructor. More...

OP1::result_type	operator() (const typename OP2::argument_type &x) const
	function call More...

Private Attributes
OP1	op1_

OP2	op2_

Detailed Description

template<class OP1, class OP2>
class OpenMS::UnaryComposeFunctionAdapter< OP1, OP2 >

Represents the function object unary adapter.

This simplest and most fundamental compose function adapter uses the result of a unary operation as input to another unary operation. For more details, please refer to the book "The C++ Standard Library" by Nicolay Josuttis. This class is implemented in order to reduce (substitute) the usage of user defined functors. You can use it for example to combine several operation in one function call. Here is an example of combining "minus 5 and multiply by 10": compose_f_gx(bind2nd(multiplies<int>(),10),bind2nd(minus<int>(), 5))

Another example of compose_f_gx_t usage is along with mem_ref_fun function to search for elements in container based on the certain element's property. Here is an example:

#include <string>
#include <vector>
#include <utility>
#include <algorithm>
using namespace std;
class Element {
 public:
  Element(const string& a) : _a(a) {}
  const string& getA() const { return _a; }
 private:
  string _a;
};
int main(int argc, char** argv) {
 Element a("4"), b("3"), c("2"), d("1");
 vector<Element> elements;
 elements.push_back(a);
 elements.push_back(b);
 elements.push_back(c);
 elements.push_back(d);
 vector<Element>::const_iterator it = find_if(elements.begin(), elements.end(),
  unaryCompose(bind2nd(equal_to<string>(), "3"), mem_fun_ref(&Element::getA)));
 if (it != elements.end())
 {
  cout << "element 3 has index " << it-elements.begin() << endl;
 }
 else
 {
  cout << "element 3 is not in the container." << endl;
 }
 return 0;
}

The Example has the following output:

element 3 has index 1

Permission to use, copy, modify and distribute this software for personal and educational use is hereby granted without fee, provided that the above copyright notice appears in all copies and that both that copyright notice and this permission notice appear in supporting documentation, and that the names of Addison Wesley Longman or the author are not used in advertising or publicity pertaining to distribution of the software without specific, written prior permission. Addison Wesley Longman and the author make no representations about the suitability of this software for any purpose. It is provided "as is" without express or implied warranty.

ADDISON WESLEY LONGMAN AND THE AUTHOR DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ADDISON WESLEY LONGMAN OR THE AUTHOR BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

Constructor & Destructor Documentation

◆ UnaryComposeFunctionAdapter()

UnaryComposeFunctionAdapter	(	const OP1 &	o1,
		const OP2 &	o2
	)

inline

Constructor.

Member Function Documentation

◆ operator()()

OP1::result_type operator() ( const typename OP2::argument_type & x ) const

inline

function call

References UnaryComposeFunctionAdapter< OP1, OP2 >::op1_, and UnaryComposeFunctionAdapter< OP1, OP2 >::op2_.

Member Data Documentation

◆ op1_

OP1 op1_

private

Referenced by UnaryComposeFunctionAdapter< OP1, OP2 >::operator()().

◆ op2_

OP2 op2_